Impeller and governor for same



Aug. 21," 19 45. MADER 2,383,002

IMPELLER AND GOVERNOR FOR SAME Filed May 5, 1943 2 Sheets-Sheet l 3nnentor Emilia/wade;-

35 m r (Ittome Aug. 21, 1945. E. A, MADER I 2,383,002

IMPELLER AND GOVERNOR FOR SAME Filed May 3, 1943 2 Sheets-Sheet 2 v Zhwentor Patented All. 21, 1945 IMPELLER AND GOVERNOR FOR SAME Emil A. Mailer, Detroit, 'Mich., assignor oi. onehalf to John Spargo, Detroit, Mich.

Application May 3, 1943, Serial No. 485,533

' Claims. (Cl. 230-120) This invention relates to impellers and particularly bladed impellers providing for automatic pitch variation of the blades.

An object of the invention is to mount a bladed impeller to deliver air or some other fluid through an-opening, and toemploy centrifugal force to establish a desired effective pitch for the blades when the impeller is driven and toprovide resilient means to position-the blades for,

jointly closing the entire opening, when the drive ceases.

Another object is to provide an impeller having its blades pivoted to permit their functioning as a closure when idle, and to associate with such impeller a centrifugal governor automatically establishing the impelling or closure positions of the blades according as the impeller is driven or idle.

Another object is to provide a highly simplifled control connection between the blades and governor of said impeller.

Another object is to provide a bladed impeller with a reinforcing rin urrounding its blades and to establish a sealing relation between such ring and a member having an opening wherein the impeller operates.

Another object is to so pivot the blades of an impeller that they coact to form a closure in a certain pivotal position and are substantially balanced in such position as regards fluid pressure applied from either side of the impeller.

These and various other objects are attained Fig. 3 is an enlarged detail View of one of the actuating connections'from the governor to a blade of the impeller.

Fig. 4 is a cross sectional view of the impeller, its governor, and surrounding installation, taken on the line 4-4 of Fig. 1.

Fig. 5 is a side elevational view of the impeller showing its blades in impelling position and showing the corresponding position of the governor.

In these views, the reference character I designates a shaft rotatively driven by an electric or other motor (not shown). Fixed on said shaft by a set screw 2 or the like is a sleeve3 fixedly carrying an impeller hub 4. Rigidly and radially projecting from said hub is a suitable number of equally spaced pivot rods 5, five thereof being employed in the illustrated construction, the

spider thus formed being reinforced by a sheet metal ring 6 engaging the outer end portions of said rods. Said ring is shown as carrying sleevetype sockets I wherein said end portions are fitted. Individually pivoted on the rod 5 and substantially bisected by. said rods are sheet metal blades 8, approximately sector-shaped, functioning alternately to impel air, and to jointly provide a closure for the opening of the ring 6. When exercising their closure function, the blades lie substantially in the rotational plane established by their pivotal axes, with approximately radial margins of adjacent blades slight- 1y lapped. This position of the blades is illustrated in Figs. 1 to 4 inclusive. For impelling air, the blades are pivoted in unison to give them a suitable pitch, as illustrated in Fig. 5. To render the blades more effective in their impelling position, it is preferred to curve the trailing margins 8a of the blades so as to extend said margins slightly outward from the pressure-applying faces of the blades. Pivotal mounting of the blades on the rods may be effected in any desired manner. In the mounting illustrated, each blade has a biseoting relation to its supporting rod, being formed with a corrugation 9 along a medial .radial line to accommodate the rod, and cylin drical bearings ID for the rod being fixed on the inner and outer portions of the blade. The inner and outer edges of the blades are preferably arcur ate and in as close proximity respectively to the hub 4 and ring 6 as is feasible without interference.

With the described impeller is associated a suitable centrifugal governor for automatically establishing the impelling or closure-forming positions of the blades, according as the impeller is driven or idle. The illustrated governor comprises a collar H fixed on the sleeve 3, a pair of weighted arms l2 pivoted on said collar and extending oppositely outward therefrom, a disk I! slidable on said sleeve. and urged toward the impeller by a spring coiled on th sleeve, swinging link connections l5 from the arm l2 to said disk, and actuating connections from the disk to the blades. Said actuating connections may take various forms, there being illustrated a quite simple provision consisting of pins Ii fixed on the disk and respectively projecting through the respective blades, each pin loosely carrying two collars ll, one at each side of the corresponding blade. The blades are formed with slightly oversized openings I8 to accommodate such pins, such openings being similarly spaced from the rods and being formed preferably in the inner end portions of the blades. The collars I'l have coned faces confronting the blades, and cotter pins I 9 engage the free end portions of the pins to maintain the assembly. This arrangement renders the blades freely pivotally responsive to sliding travel of the disk l3.

The impeller. is coaxial with and rotates substantially within a circular opening 20 formed in a sheet metal plate 2 I, mounted in any desired manner. It is desired to avoid air flow past the outer edge of the ring 6, and such flow is avoided by extending said ring some distance into an annular sealing chamber 22 formed between the plate 2| and a companion sheet metal plate 23. The two said plates are in close proximity to the ring '6 but sufficiently clear the latter to avoid interference with its rotation. As illustrated, the plates 2| and 23 are rectangular and rigidly interconnected at their outer margins by screws 24.

In use of the described construction, the spring [4 has its maximum expansion when the impeller is at rest, this expansion being limited by the lapping interengagement of the blades. Thus said interengagement is maintained under a pressure adequate to-avoid rattling of the blades or leakage of air between them. Since they occupy a balanced relation to their pivot rods, they are able to resist considerable air or other fluid pressures acting from either side of the impeller.

With the impeller at rest (Fig. 4) the weighted arms l2 have a considerable inclination toward the impeller. Upon establishing a drive, said arms are centrifugally shifted to their position shown in Fig. 5, drawing the disk I3 toward the collar II and pivoting the blades correspondingly on their supporting rods. As the arms I2 approach a transverse relation to the sleeve 3, the coned faces of the collars l'l engage opposite faces of the blades and limit their pivotal play. Thus a predetermined pitch is established for the blades and maintained while the impeller is driven. Upon cutting off the drive, the spring It returns the blades to their closure-forming position.

In adapting the blades to jointly form a closure,

when the impeller is at rest, there is eliminated necessity for pressure-responsive pivotal iouvers, now commonly employed to close or open air passages according as a fan delivering air to such passages is idle or driven.

When the described construction is installed in an exterior wall for ventilating purposes, the seal established within the annular chamber 22 is particularly vital in preventing rain, snow, dust, and exterior air from gaining'access to a building. In such an installation, the lapped relation of the blades is also particularly vital for same reasons.

While the construction has been described as applied to alternately impel air and close an opening through which the air is impelled, it is obvious that the same functions may be exercised with respect to various other fluids. It is further tobe noted that the construction may be installed at any desired point within a duct as well as within or upon a wall.

What I claim is:

1. The combination with an impeller comprising a rotary carrier having a fluid passage. a plurality of blades, and means pivoting said blades on the carrier to alternatively close said passage or impel air through the passage, of means yieldably urging the blades to their closure position, and a centrifugal speed responsive device for establishing the impelling position of the blades, including a member actuable to and from the impeller, and a plurality of pins rigidly mounted on said member and engaged in openings of the blades to subject the blades to the speed responsive device.

2. A rotary fluid impeller comprising a hub, a plurality of rods rigidly carried by and outwardly projecting from said hub, a sheet metal annulus interconnecting the outer end portions of said rods, and extending outwardly beyond the rods, a plurality of blades respectively pivoted on the respective rods to alternatively close the opening between said annulus and hub or impel air through said opening, means yieldably urging said blades to their closure position, means for actuating the blades in unison to their impelling position, and sealing means laterally coacting with said annulus to prevent air flow across the periphery of the impeller.

3. The combination with a blade rotative about an axis at one end of said blade and means pivoting the blade for regulation of its pitch with respect to its plane of rotation, of a member slidable to and from the blade along said axis, a spring urging said member in one direction, means for centrifugally shifting such member in the opposlte direction, a pin rigidly projecting from the sliding member toward the blade and at least approximately parallel to said axis, the blade having an opening accommodating said pin, and abutments on the pin at opposite sides of the blades presenting substantially coned faces to the blade, whereby the sliding member is adapted to regulate the pitch of the blade.

4. The combination with a rotary impeller comprising a hub, a plurality of rods rigidly carried by and outwardly projecting from the hub, a sheet metal annulus interconnecting the outer end portions of said rods and disposed in the rotational plane of the impeller, a plurality of blades respectively pivoted by the respective rods to alternatively close the opening between the annulus and hub or impel air through said opening, means yieldably urging the blades to their closure position, and means for actuating the blades in unison to their impelling position, of a pair of plates adjacent and substantially parallel to said annulus, at opposite sides of the annulus and fixed with respect to impeller rotation, said plates resisting air flow across the periphery of the impeller.

5. In the combination as set forth in claim 4, socket members for said rods carried by said annulus and occupying a circular opening formed by at least one of said plates.

MIL A. MADER. 

